Origin

Insects have bodies that are divided into segments, and segments are the basic idea behind the word. Insect was formed in the 17th century from Latin animal insectum ‘segmented animal’, and originally referred to any small cold-blooded creature with a segmented body, for example, a spider, not just what we would call insects. The root word is secare ‘to cut’, which gave us dissect (late 16th century), section (Late Middle English), and segment (late 16th century).